Font diacritics have different size when publish in iOS

Hi, I've been having trouble with characters with diacritics (accents) such as ṁ and ś which appear slightly larger than the normal characters. However, characters such ā and ī appear to be the same size as the others. Any way of fixing this issue. Please see photo attached. The problem appears in the question text but not in the answer texts. Thanks in advance. Aris